Using a mouse model, we have been attempting for several years to understand some of the immunological events which participate in and help to determine the severity of influenza virus induced inflammatory lung disease. Our previous studies and that of several other groups have indicated that the thymus dependent immunological system has an important role in eradicating virus and in preventing widespread dissemination of virus from the lung, but at the same time contributing to the inflammation which occurs locally in the lung. Our future studies will concentrate on the effects of vaccines and therapeutic adoptive immunization of intact or compromised mice with lymph node and spleen cells, subpopulations of these cells, or other materials from previously vaccinated or inoculated donor mice, and intranasal challenge of the recipients with influenza virus. Indices of infection and inflammaton, virus titers and immunolgic responses will be quantitated and correlated. By understanding how T-lymphocytes and factors which affect cell mediated immunity modulate influenza disease, a more ratioal approach to the development of influenza vaccines and prophylactic treatment of influenza may be obtained.